Professors Karlin and McGregor will continue their study of polymorphic clines, with both discrete and continuous models. It will be particularly interesting to determine whether selective clines differ qualitatively in transient or equilibrium behavior from non-selective ones. They also expect to devote more time to polygenic models and problems of quantitative inheritance. An important goal is to obtain better insight into the role of epistasis in the inheritance of quantitative traits. A new technique for reconstruction of evolutionary trees has been set up, which allows testing the validity of evolutionary hypotheses. These methods will be extended and applied to populations of special interest by Professor Cavalli, with the assistance of Dr. Carmelli. Professors Cavalli and Feldman will continue their work on genetic systems with cultural factors.